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公开(公告)号：US11269037B2
公开(公告)日：2022-03-08
申请号：US16754771
申请日：2018-10-05
IPC分类号： G01R33/567 , G01R33/48 , G01R33/561
摘要： The invention relates to a method of MR imaging of an object (10) placed in an examination volume of a MR device (1). It is an object of the invention to enable MR imaging using a radial (or spiral) acquisition scheme with a reduced level of motion artefacts. The method of the invention comprises the following sequence of steps: —detecting a momentary motion—induced displacement (Δ) of the object (10); —attributing the detected displacement (A) to a motion state (M1-M5), each motion state (M1-M5) corresponding to one of a plurality of contiguous ranges of displacements (Δ); —determining angular coordinates of a radial or spiral k-space profile by incrementing the angular coordinates individually for each motion state (M1-M5) starting from initial angular coordinates; —acquiring the k-space profile; —repeating steps a-d a number of times; and —reconstructing an MR image from at least the k-space profiles attributed to one of the motion states (M1-M5). Moreover, the invention relates to a MR device (1) for carrying out this method as well as to a computer program to be run on a MR device (1).
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公开(公告)号：US11241162B2
公开(公告)日：2022-02-08
申请号：US15303535
申请日：2015-03-31
IPC分类号： A61B5/055 , A61B5/00 , G01R33/565 , G06T7/00 , G01R33/563 , G01R33/56 , G01R33/48
摘要： A method of operating a magnetic resonance imaging system (10) with regard to acquiring multiple-phase dynamic contrast-enhanced magnetic resonance images, the method comprising steps of acquiring (48) a first set of magnetic resonance image data (xpre) prior to administering a contrast agent to the subject of interest (20), by employing a water/fat magnetic resonance signal separation technique, determining (52) a first image of the spatial distribution of fat (Ipre) of at least the portion of the subject of interest (20), acquiring (50) at least a second set of magnetic resonance image data (x2) of at least the portion of the subject of interest (20) after administering the contrast agent to the subject of interest (20), by employing a water/fat magnetic resonance signal separation technique, determining (54) at least a second image of the spatial distribution of fat (I2ph) of at least the portion of the subject of interest (20), applying (56) an image registration method to the second image of the spatial distribution of fat (I2ph) with reference to the first image of the spatial distribution of fat (Ipre) for correcting a potential motion of the subject of interest (20); and a magnetic resonance imaging system (10) having a control unit (26) that is configured to carry out steps (56-64) of such a method; and a software module (44) for carrying out such a method, wherein the method steps (56-64) to be conducted are converted into a program code that is implementable in a memory unit (30) and is executable by a processor unit (32) of the magnetic resonance imaging system (10).
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公开(公告)号：US11092659B2
公开(公告)日：2021-08-17
申请号：US16498555
申请日：2018-03-30
IPC分类号： G01R33/483 , G01R33/24 , G01R33/44 , G01R33/48 , G01R33/56 , G01R33/565
摘要： A magnetic resonance imaging (MRI) system (100) includes a memory (134) for storing machine executable instructions (140) and magnetic resonance fingerprinting (MRF) pulse sequence commands (142) which cause the MRI system to acquire MRF magnetic resonance data (144) according to an MRF protocol. The pulse sequence commands are configured for acquiring the MRF magnetic resonance data in two-dimensional slices (410, 412, 414, 416, 418, 420), having a slice selection direction. A train of pulse sequence repetitions includes a sampling event where the MRF data is repeatedly sampled. Execution of the machine executable instructions causes a processor to control the MRI system to: acquire (200) the MRF magnetic resonance data; construct (202) a series (148) of at least one magnetic resonance parameter value for each voxel of the two dimensional slices; and calculate (204) a composition (502, 504, 506, 508) of each of a set of predetermined substances within two or more sub-voxels (306, 308) for each voxel of the two dimensional slices using a sub-voxel magnetic resonance fingerprinting dictionary (150) for each of the two or more sub-voxels and the series of the at least one magnetic resonance parameter value. Each voxel in the slice selection direction is divided into two or more sub-voxels.
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公开(公告)号：US10788556B2
公开(公告)日：2020-09-29
申请号：US16072940
申请日：2017-02-06
IPC分类号： G01R33/56 , G01R33/46 , G01R33/48 , G01R33/54 , G01R33/561
摘要： A magnetic resonance imaging system (100) acquires magnetic resonance data (142) from a subject (118) within a measurement zone (108). Pulse sequence commands (140) control the magnetic resonance imaging system to acquire the magnetic resonance data according to a magnetic resonance fingerprinting protocol. The pulse sequence commands are configured for controlling the magnetic resonance imaging system to repeatedly generate an RF pulse train (300) and acquire the magnetic resonance data as multiple k-space traces. The machine executable instructions causes the processor to: sequentially acquire (200) the multiple k-space traces of magnetic resonance data by controlling the magnetic resonance imaging system with pulse sequence commands and calculate (202) the abundance of each of a set of predetermined substances for k-space traces that are acquired after a predetermined number of k-space traces of the multiple k-space traces has been acquired and the acquired magnetization has reached a steady state. The abundance of each of a set of predetermined substances is determined by comparing the magnetic resonance data with a steady state magnetic resonance fingerprinting dictionary (144) which contains a listing of calculated magnetic resonance signals in response to the RF pulse train for a set of predetermined substances.
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15.发明授权公开(公告)号：US10509086B2
公开(公告)日：2019-12-17
申请号：US15735422
申请日：2016-06-08
IPC分类号： G01R33/46 , G01R33/30 , G01R33/31 , G01R33/3875 , G01R33/389 , G01R33/36 , G01R33/465 , G01R33/48
摘要： The invention provides for a method of operating an instrument (100). The instrument comprises a magnetic resonance system (102) for measuring dictionary magnetic resonance data (154) from a measurement zone (108). The magnetic resonance system comprises a magnet (104) for generating a main magnetic field within the measurement zone. The magnetic resonance system comprises a test fixture (124) for holding a test sample (132) within the measurement zone. The test fixture comprises a supplementary magnetic field coil (126) and a magnetic resonance antenna (128). The method comprises the steps of repeatedly: choosing (200) an electrical current; supplying (202) the electrical current to the supplementary magnetic field coil to adjust the main magnetic field within the measurement zone; acquiring (204) the dictionary magnetic resonance data from the test sample with the magnetic resonance antenna by controlling the magnetic resonance system according to a magnetic resonance fingerprinting technique; and appending (206) the dictionary magnetic resonance data to a magnetic resonance fingerprinting dictionary (156).
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公开(公告)号：US09964615B2
公开(公告)日：2018-05-08
申请号：US14778124
申请日：2014-03-12
IPC分类号： G01R33/48 , G01R33/561 , G01R33/565
CPC分类号： G01R33/4824 , G01R33/4828 , G01R33/561 , G01R33/5611 , G01R33/56545
摘要： The invention relates to a method of MR imaging of an object (10) placed in an examination volume of a MR device (1). The method comprises the steps of: subjecting the object (10) to an imaging sequence for acquiring MR signal data, wherein the MR signal data are acquired as a function of k-space position and time by using an irregular k-space sampling pattern with sub-sampling of k-space; reconstructing MR image data from the MR signal data, which MR image data comprise spatial dimensions and a frequency dimension, sparsity of the MR image data in a transform domain being exploited for suppressing sub-sampling artefacts in the MR image data. Moreover, the invention relates to a MR device (1) and to a computer program.
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公开(公告)号：US20160291106A1
公开(公告)日：2016-10-06
申请号：US14778124
申请日：2014-03-12
IPC分类号： G01R33/48 , G01R33/565 , G01R33/561
CPC分类号： G01R33/4824 , G01R33/4828 , G01R33/561 , G01R33/5611 , G01R33/56545
摘要： The invention relates to a method of MR imaging of an object (10) placed in an examination volume of a MR device (1). The method comprises the steps of: subjecting the object (10) to an imaging sequence for acquiring MR signal data, wherein the MR signal data are acquired as a function of k-space position and time by using an irregular k-space sampling pattern with sub-sampling of k-space; reconstructing MR image data from the MR signal data, which MR image data comprise spatial dimensions and a frequency dimension, sparsity of the MR image data in a transform domain being exploited for suppressing sub-sampling artefacts in the MR image data. Moreover, the invention relates to a MR device (1) and to a computer program.
摘要翻译： 本发明涉及放置在MR装置（1）的检查体积中的物体（10）的MR成像方法。 该方法包括以下步骤：对物体（10）进行成像序列获取MR信号数据，其中通过使用不规则的k空间采样模式来获取MR信号数据作为k空间位置和时间的函数， k空间的次采样; 从MR信号数据重建MR图像数据，MR图像数据包括空间维度和频率维度，被用于抑制MR图像数据中的子采样伪像的变换域中的MR图像数据的稀疏度。 此外，本发明涉及MR设备（1）和计算机程序。
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